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ISIS Neutron and Muon Source

The ISIS Neutron and Muon Source is a world-leading pulsed spallation neutron and muon facility located at the Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory in Oxfordshire, United Kingdom, dedicated to probing the atomic-scale structure and dynamics of materials for applications in physical, chemical, life, and engineering sciences.^[1] Operated by the STFC as the UK's national research center for neutron and muon techniques, it enables non-destructive studies of complex systems, from batteries and quantum materials to biological molecules and cultural artifacts, supporting 1,673 unique users in 2025 from academia and industry across more than 30 countries.^[2]^[3] Established in 1984 with the production of its first neutrons on December 16 of that year, ISIS originated from repurposed infrastructure of the earlier Nimrod synchrotron at the Rutherford Appleton Laboratory and was officially named and opened by Prime Minister Margaret Thatcher in October 1985.^[4] Key milestones include energy upgrades from an initial 550 MeV to 800 MeV by 1990, the addition of a second target station in 2008 to expand neutron capabilities with short-pulse beams, and ongoing enhancements like the £93 million Endeavour programme, which is developing new instruments such as Super MuSR and HRPD-X for completion by 2028.^[4]^[5] These developments have positioned ISIS as one of the world's most powerful pulsed sources, with an average accelerator availability of 87.5% and operations running in cycles totaling around 200 days per year.^[3] At its core, ISIS operates an 800 MeV proton synchrotron accelerator that delivers intense pulses at 50 Hz onto tungsten spallation targets, generating neutrons through nuclear reactions and muons via a secondary carbon foil, which are then moderated and directed along beamlines to experimental instruments.^[6] The facility features two target stations: the original for long-pulse neutrons and muons, and the second for short-pulse neutrons optimized for high-resolution studies.^[4] This setup supports a diverse suite of over 30 neutron and muon instruments, including diffractometers like HRPD for powder diffraction, spectrometers like MAPS for inelastic scattering, and imaging tools for engineering applications, allowing researchers to apply for free beamtime through a competitive peer-review process.^[7] In 2025, ISIS received 1,402 proposals and delivered 3,879 instrument days, resulting in 559 peer-reviewed publications with significant international collaboration.^[3] ISIS's research has profound impacts, addressing global challenges such as sustainable energy through studies on battery degradation and hydrogen storage, quantum technologies via investigations of spin liquids, and health innovations like mRNA delivery systems.^[8]^[3] The facility fosters a vibrant user community of approximately 3,000 scientists yearly, including 37% students, and engages industry partners—reaching 90 companies in 2025—while contributing to economic growth with an estimated £0.4 billion in future impacts from prior research.^[2]^[3] Looking ahead, initiatives like the ISIS-II project are exploring next-generation designs to sustain leadership in neutron and muon science beyond 2040.^[9]

Overview and Background

Facility Description

The ISIS Neutron and Muon Source is located at the Science and Technology Facilities Council (STFC) Rutherford Appleton Laboratory on the Harwell Science and Innovation Campus in Oxfordshire, United Kingdom.^[2] It is owned and operated by the STFC as part of UK Research and Innovation (UKRI), serving as the UK's national facility for neutron and muon-based materials research.^[2] The facility provides non-destructive techniques to probe atomic structures and dynamics in fields ranging from physics to biology, enabling scientists worldwide to conduct experiments at the atomic scale.^[2] At the core of the facility is the ISIS synchrotron, an 800 MeV proton accelerator that delivers intense pulses of protons at a rate of 50 Hz.^[10] These protons strike a tungsten target to produce neutrons through spallation, while muons are generated via the decay of pions produced in a secondary process.^[6] This pulsed beam setup supports a suite of over 30 neutron and muon instruments, allowing time-resolved studies of material properties.^[7] Annually, the facility supports approximately 1,673 unique users through 1,402 approved proposals, with beam time allocated through a competitive, peer-reviewed proposal process.^[3] Access is free for academic researchers, whose results must be published openly, while industry users can request confidential sessions.^[11] The user community includes 37% students and researchers from academia, alongside collaborators from industry—such as the 90 companies hosted each year—and international partners, with 73.3% of journal publications involving international collaboration from over 30 countries.^[3]

Fundamental Physics

The ISIS Neutron and Muon Source relies on the spallation process for neutron production, in which high-energy protons accelerated to 800 MeV in the synchrotron strike a tungsten target, dislodging neutrons from the atomic nuclei through nuclear collisions.^[10] Each incident proton typically ejects 25–30 fast neutrons in this process, resulting in a yield of approximately 6–8 × 10^{14} neutrons per pulse given the facility's beam of about 2.5 × 10^{13} protons per pulse.^[12]^[13] These fast neutrons, initially possessing energies comparable to the proton beam, are then moderated—slowed down—to thermal or cold energies suitable for scattering experiments; light water moderators produce a thermal neutron spectrum around 25 meV, while liquid hydrogen moderators yield a colder spectrum peaking below 5 meV.^[10] Muon production at ISIS occurs via a secondary interaction where a fraction (2–3%) of the 800 MeV proton beam is directed onto a graphite target, generating charged pions through proton-carbon collisions; these pions, with a mean lifetime of 26 ns, subsequently decay into positive and negative muons along with neutrinos.^[14] The resulting muons, which inherit polarization from the pion decay, are captured, accelerated, and transported to beamlines for implantation in samples, with delivery energies tunable up to 80 MeV to enable depth-profiling and spectroscopy in condensed matter studies.^[14]^[15] The pulsed operation of the ISIS accelerator, delivering proton bunches at a 50 Hz repetition rate, underpins the time-of-flight (TOF) technique central to neutron scattering measurements.^[6] In TOF, the known start time of each neutron pulse allows determination of individual neutron energies from their flight times to detectors, providing broad wavelength coverage and energy resolution without the need for mechanical velocity selectors or choppers.^[12] This pulsed structure enhances efficiency for dynamic experiments, as the short pulse width (∼100 ns) minimizes overlap in arrival times for neutrons spanning thermal to epithermal energies. The efficiency of spallation neutron production scales approximately with proton energy as Y_n \approx k \cdot E_p^{1.8}, where Y_n is the neutron yield, E_p is the proton energy in GeV, and k is an empirical constant dependent on target material; at ISIS's 0.8 GeV, this scaling underscores the choice of energy for balancing yield and accelerator feasibility.^[16]

Historical Development

Origins and Establishment

The conception of the ISIS Neutron and Muon Source emerged in the 1970s at the Rutherford Appleton Laboratory, driven by the need to replace the aging Nimrod proton synchrotron, which had operated from 1964 to 1978 but suffered from reliability issues and insufficient neutron flux for advanced materials research.^[4] Nimrod's closure highlighted the demand for a pulsed spallation neutron source capable of delivering higher neutron brightness, leveraging accelerator technology to produce intense, short pulses of neutrons via proton bombardment of a heavy metal target.^[17] UK government approval for the project came in 1977, with construction funded through the Science Research Council (predecessor to the Science and Technology Facilities Council), utilizing repurposed infrastructure from Nimrod, including its synchrotron hall and some magnets, to accelerate development and reduce costs.^[4]^[17] Officially established in 1984, the facility featured a proton accelerator system designed for 800 MeV, comprising a 70 MeV linear accelerator (linac) originally built in the 1970s as a Nimrod injector, a rapid-cycling synchrotron, and a single target station (TS1) using a depleted uranium target to generate neutrons through spallation. The proton beam was first commissioned on December 16, 1984, producing the initial neutrons at an energy of 550 MeV and a repetition rate of 50 Hz, with an initial beam power of approximately 100 kW.^[4]^[18] The facility was formally opened on October 18, 1985, by Prime Minister Margaret Thatcher, who named it ISIS—standing for Intense Spallation Source—a moniker chosen to evoke the Egyptian goddess of magic and the nearby River Isis (the upper Thames), replacing its provisional designation as the Spallation Neutron Source.^[17]^[19] Early operations focused on achieving reliable neutron production for initial experiments in physics and materials science, with the first neutron scattering experiments commencing in 1985 at TS1 beamlines.^[4] However, challenges included stabilizing the 50 Hz pulsing rate amid synchrotron injection inefficiencies and ensuring target durability, as the uranium targets experienced swelling and degradation under the intense proton flux, necessitating frequent replacements and material refinements.^[4] These hurdles were gradually addressed through incremental upgrades, such as increasing beam energy to 750 MeV by 1987 and to 800 MeV by 1990, laying the groundwork for sustained operations while prioritizing conceptual advancements in spallation-based neutron generation over exhaustive performance metrics.^[4]

Major Expansions and Upgrades

Following its initial operations, the ISIS facility underwent key upgrades in the 1990s to enhance its capabilities, including an increase in synchrotron beam current to 200 μA by 1994, achieving an average beam power of approximately 160 kW. This improvement, driven by accelerator enhancements such as upgraded RF systems and ion source developments, significantly boosted neutron production efficiency via spallation processes. Concurrently, the muon program expanded from its inception, with the first dedicated muon beamline operational since 1987 using a graphite production target; a major rebuild of the primary beamline in 2008 quadrupled the available muon flux, enabling broader applications in materials science.^[20] The most transformative infrastructural project was the Second Target Station (TS2), approved for funding in 2003 at a total cost of £170 million, with construction spanning 2004 to 2008 and full operations commencing in 2009. Unlike the original Target Station 1, TS2 was designed to deliver short-pulse neutrons optimized for time-of-flight techniques in areas like soft condensed matter, providing up to 20% of the proton beam pulses for higher-resolution studies. In 2011, a further £21 million investment from the UK government supported the construction of four new instruments on TS2, along with upgrades to detectors and the target reflector system, while extending the facility's projected lifespan from 2005 to 2030.^[20]^[21] Subsequent optimizations focused on accelerator reliability and neutron flux, with beam power reaching approximately 200 kW through incremental improvements. In 2023, the £93 million Endeavour programme was approved to develop advanced instruments such as Super MuSR and HRPD-X, with user operations targeted for 2028. Additional enhancements included the commissioning of a decoupled methane moderator at TS2 in June 2024 to improve resolution on the WISH instrument and the replacement of the TS2 proton beam window in January 2025. Looking ahead, planning documents outline a phased decommissioning of the facility by 2040 to manage radioactive waste from spallation targets, with site restoration costs estimated at £9 million to £16 million.^[20]^[3]^[5]

Research and Applications

Scientific Disciplines

The ISIS Neutron and Muon Source supports research across diverse scientific disciplines by leveraging neutron and muon beams to probe the atomic and molecular structures, dynamics, and properties of materials in a non-destructive manner. These capabilities enable investigations that are complementary to other techniques, such as X-ray diffraction, by providing sensitivity to light elements like hydrogen and magnetic interactions.^[22] In physics and materials science, neutrons and muons facilitate the study of crystal structures, magnetic ordering, and quantum phenomena in materials like superconductors and magnets. For instance, neutron scattering reveals lattice dynamics and phase transitions, while muons help characterize spin correlations and electronic properties at the atomic scale. These approaches are crucial for advancing understanding of condensed matter systems and developing next-generation quantum technologies.^[23]^[24] Chemistry and engineering research at ISIS focuses on molecular-level interactions in functional materials, including catalysts for chemical reactions, battery electrodes for energy storage, and polymers for structural applications. Neutrons excel at tracking hydrogen positions and bond vibrations, which inform the design of more efficient and durable materials for industrial processes.^[22]^[25] In biology and soft matter sciences, neutron techniques elucidate the conformations of proteins, the organization of lipid membranes, and the self-assembly in drug delivery systems. By contrast-matching with deuterium labeling, researchers can isolate specific components in complex biological environments, yielding insights into molecular motions and interactions relevant to health and biotechnology.^[22]^[26] Archaeology and cultural heritage studies benefit from the non-invasive nature of neutron-based analysis to examine the composition and degradation of ancient artifacts, such as metals and ceramics, without causing damage. This allows for the identification of manufacturing techniques and environmental impacts on historical objects, supporting preservation efforts and historical interpretations.^[27] Muon applications, including muon spin rotation (μSR), provide specialized probes for magnetism in diverse materials and depth-resolved profiling in semiconductors. In μSR, implanted muons act as sensitive indicators of local magnetic fields and spin dynamics, while low-energy muons enable layer-by-layer analysis of dopant distributions and defects in electronic materials.^[24] Access to ISIS beam time is granted through a rigorous peer-review process conducted by Facility Access Panels, comprising international experts who assess proposals on scientific merit, feasibility, and potential impact. This system ensures equitable allocation to a global user community of approximately 3,000 scientists yearly, with 1,673 unique users in 2025 (37% students), resulting in 559 peer-reviewed publications that year, with 73.3% featuring international co-authors.^[3]^[2]

Key Achievements and Impacts

One of the landmark discoveries enabled by research at the ISIS Neutron and Muon Source was the elucidation of the structure and dynamics of buckminsterfullerene (C60), conducted in the 1990s using neutron diffraction and inelastic scattering techniques.^[28] Similarly, in the 1980s, neutron spectroscopy at ISIS revealed the crucial role of magnetic interactions in high-temperature superconductors, advancing the understanding of cuprate materials and contributing to the broader field recognized by the 1987 Nobel Prize in Physics.^[29]^[28] In energy research, ISIS studies have provided insights into battery degradation mechanisms, such as the three-phase discharge processes in sodium-ion batteries and the ageing of niobium-based anodes, supporting the development of longer-lasting energy storage solutions.^[25]^[30] Neutron and muon techniques have also examined hydrogen dynamics in storage materials, including cycling in metal hydrides for Toyota's fuel cell applications, aiding the transition to a hydrogen economy.^[31]^[25] Biological advances from ISIS include neutron scattering investigations into mRNA vaccine delivery, where small-angle neutron scattering on beamlines like Zoom and SANS2D revealed the formation of stable polyethylenimine-saRNA nanoparticles, enhancing efficacy and manufacturability for influenza vaccines in collaboration with BioNTech and EMBL.^[32] Additionally, neutrons have elucidated enzyme functions, such as the relay-like electron transfer in cytochrome P450 reductase, which is key to drug metabolism processes.^[33] Industrial applications have been significant, with ISIS collaborating with 90 companies (as of 2025), including principal investigators from sectors like pharmaceuticals and aerospace, leading to innovations such as improved drug delivery systems by Unilever and enhanced inertia friction welding for Rolls-Royce aircraft engines used in Airbus and Boeing models.^[34]^[3]^[35] Over its lifetime, ISIS research has contributed to more than 10,000 peer-reviewed publications by 2019, with approximately 600 new publications annually across disciplines, fostering high-impact science cited thousands of times.^[35] In 2025, ISIS scientists received the Royal Society of Chemistry's Dalton Horizon Prize for pioneering hybrid glasses and the Materials Chemistry Horizon Prize for developing ChemDataExtractor, a chemistry-aware AI software for materials discovery.^[3]^[36]^[37] Public engagement efforts at ISIS reached 8,260 participants in 2025 through nearly 50 events, including school programs and work experience for 32 students, inspiring the next generation in STEM.^[3]

Instrumentation

Target Station 1

Target Station 1 (TS1) is the original neutron production facility at the ISIS Neutron and Muon Source, optimized for delivering long-pulse neutron beams that enable high-resolution studies of crystalline and hard materials. It produces thermal and cold neutrons through spallation of an 800 MeV proton beam on a tantalum-clad tungsten target, moderated to provide neutrons suitable for diffraction, spectroscopy, and imaging applications. TS1 supports approximately 25 neutron instruments, focusing on high flux and precision measurements for fields such as materials science, engineering, and cultural heritage analysis.^[38] Key instruments on TS1 include the General Materials Diffractometer (GEM), which performs high-intensity, high-resolution neutron diffraction and pair distribution function analysis for studying both crystalline and disordered materials. The High-Resolution Powder Diffractometer (HRPD) offers exceptional resolution for structural refinements in powder samples, utilizing a long flight path from the 110 K methane moderator. POLARIS, a time-of-flight powder diffractometer, is tailored for engineering applications, enabling rapid analysis of large samples under applied stress or temperature. For spectroscopy, MARI serves as a direct-geometry chopper spectrometer for inelastic neutron scattering, probing magnetic and lattice dynamics in materials. IRIS and OSIRIS facilitate quasi-elastic and low-energy inelastic scattering studies, particularly for dynamics in hydrogenous systems like polymers and biomolecules. ENGIN-X specializes in strain scanning for residual stress measurements in engineering components, while VESUVIO employs deep inelastic neutron scattering to investigate momentum distributions in light elements such as hydrogen. Additionally, the Italian Neutron Experimental Station (INES) supports non-destructive archaeometric analysis, including phase identification and elemental mapping in artifacts without sample preparation.^[39]^[40]^[41]^[42]^[43]^[44]^[45]^[46] The neutron beams from TS1 cover energies from approximately 10 meV to 1 eV, encompassing cold (below 10 meV) and thermal regimes, with a typical flux of around 10^8 neutrons per cm² per second at sample positions, enabling statistically robust data collection over extended pulse durations. This configuration prioritizes resolution over peak brightness, making it ideal for detailed structural and dynamic investigations in dense, hard materials. A unique aspect of TS1 is its integration with muon production via a preceding graphite target, allowing hybrid neutron-muon experiments that combine structural insights from neutrons with electronic and magnetic information from muons on the same sample setup.^[47]^[48]

Target Station 2

Target Station 2 (TS2) at the ISIS Neutron and Muon Source is optimized for the production of cold neutrons with short pulse durations, enabling high-resolution studies of dynamics in complex materials. Operating at a repetition rate of 10 Hz, it delivers protons at 800 MeV and 60 μA to a tungsten target, resulting in a power dissipation of 48 kW and neutron pulses from decoupled moderators with widths of 30–50 μs, which can be shaped down to approximately 10 μs using disk chopper systems for enhanced time-resolved measurements.^[49]^[14] The station supports around 11 neutron instruments, with a typical flux on the order of 10^7 n/cm²/s, particularly suited for probing slow dynamics in soft matter systems such as nanomaterials, polymers, and liquids.^[50] First operational in 2008, TS2 expanded the facility's capacity for condensed matter research by providing brighter beams of long-wavelength neutrons compared to the higher-repetition-rate Target Station 1. Key instruments on TS2 include several specialized for diffraction, scattering, and imaging techniques. The Wide-angle and Inelastic Neutron spectrometer (WISH) offers high-resolution powder diffraction for crystallographic studies of magnetic and structural properties in materials. NIMROD, the Near and InterMediate Range Order Diffractometer, enables wide-angle diffraction over lengths from atomic to nanometer scales, ideal for disordered materials like glasses and liquids. The LET direct-geometry chopper spectrometer uses counter-rotating disk choppers to monochromate the beam, achieving energy resolutions from 20 μeV to 500 μeV for quasi-elastic and inelastic scattering in magnetic and structural dynamics.^[51] IMAT, the Imaging and Materials Testing beamline, combines neutron imaging with diffraction tomography for non-destructive analysis of engineering components and cultural artifacts.^[52] Small-angle neutron scattering (SANS) instruments on TS2, such as SANS2d and LARMOR, facilitate investigations into biological macromolecules, self-assembly in polymers, and soft condensed matter structures, with LARMOR additionally supporting spin-echo and precession techniques for dynamics over broad length and time scales.^[50] ZOOM provides time-of-flight strain mapping for engineering applications in residual stress analysis.^[53] Reflectometry instruments like OFFSPEC, added in 2011, enable high-throughput studies of interfaces in liquid systems, including air/liquid and liquid/liquid boundaries relevant to surfactants and biomolecules. The disk chopper systems, exemplified by those on LET and other spectrometers, allow precise pulse shaping to balance flux and resolution, making TS2 particularly effective for time-resolved experiments in soft matter and nanomaterials research.^[51]

Muon-Specific Beamlines

The muon-specific beamlines at the ISIS Neutron and Muon Source are dedicated facilities located at Target Station 1 (TS1), where polarized muons are produced via the decay of pions generated by the interaction of the 800 MeV proton beam with a graphite target.^[54] These beamlines deliver muons to spectrometers for condensed matter research, distinct from neutron instrumentation, with a total flux of approximately $4 \times 10^{8} muons per second.^[24] Positive muons, which serve as magnetic probes and proton analogs, have a decay lifetime of 2.2 µs and are highly spin-polarized (>99%).^[24]^[55] The primary technique enabled by these beamlines is muon spin relaxation (μSR), which measures local magnetic fields and dynamics in materials without interference from nuclear magnetism, using surface muons with momentum of about 28 MeV/c (kinetic energy ~3.8 MeV).^[24]^[55] This allows implantation depths up to ~160 mg/cm², suitable for probing thin films and bulk samples. Applications focus on quantum materials, including skyrmions and frustrated magnets, semiconductors for charge transport, and catalysis via hydrogen site studies, representing ~10% of ISIS experiments.^[24] Key beamlines include MuSR, a general-purpose spectrometer for magnetism and superconductivity via spin relaxation, equipped with 64 detectors, rotatable for longitudinal and transverse fields up to 3000 G, and temperatures from 40 mK to 1000 K.^[56] EMU specializes in surface muon experiments for thin films, featuring 96 detectors, longitudinal fields up to 5000 G, and an extended temperature range of 50 mK to 1500 K for zero- and low-field μSR.^[57] HiFi, a high-intensity forward instrument, supports applied longitudinal fields to 5 T with a superconducting split-pair magnet, enabling RF decoupling and studies of fluctuations, correlations, and phase diagrams in quantum systems across temperatures from 30 mK to 1500 K.^[58]

Recent Developments and Future Prospects

Ongoing Upgrades and Programmes

The Endeavour Programme, launched as part of the UK Research and Innovation (UKRI) strategy, represents a £90 million investment spanning 2021 to 2028 aimed at enhancing the capabilities of the ISIS Neutron and Muon Source through nine approved projects.^[59]^[3] This initiative focuses on developing new instruments and upgrading existing ones to meet evolving research demands in materials science and beyond. Key components include the Super MuSR (Multi-Use Spectrometer for High-Rate Observations of Materials), which will deliver enhanced muon flux and time resolution for studying smaller samples in fields like quantum materials; the HRPD-X, a next-generation high-resolution powder diffractometer set to set global benchmarks in diffraction science with improved resolution and sample throughput; and broader detector upgrades across multiple beamlines to boost sensitivity and data quality.^[5]^[60] Production of Super MuSR detectors commenced in summer 2025, with both Super MuSR and HRPD-X targeted for user operation by mid-2028.^[3] In 2025, several instrument-specific enhancements were completed or advanced, underscoring ongoing efforts to optimize performance. New in-house-built diffraction detectors were installed on the IMAT (Imaging and Materials Analysis) beamline, enabling high-resolution imaging for engineering and materials research, with a second tranche planned for 2026.^[3] On the EMU (Emu Muon) beamline, a novel decay positron degrader was designed and installed, improving data quality by up to 50% for muon spectroscopy experiments on semiconductors and catalysts.^[3] Additionally, the OSIRIS secondary spectrometer upgrade, featuring advanced silicon analysers, is scheduled for installation in January 2026 and commissioning in May or June 2026, promising a fivefold increase in productivity for inelastic neutron scattering studies of energy materials.^[3] Sustainability initiatives gained momentum in 2025, with the launch of a D₂O (heavy water) recovery and recycling project led by a dedicated team to reduce environmental impact and operational costs at the facility.^[3] This effort complements broader efficiency measures, such as the delivery of 3,879 instrument days during the 2024–2025 cycle, supporting 1,402 submitted proposals and maintaining high uptime despite global challenges.^[3] The year also highlighted growing community engagement through awards recognizing scientific excellence. ISIS scientists contributed to two 2025 Royal Society of Chemistry (RSC) Horizon Prizes: David Keen as part of the Dalton Horizon Prize-winning team for advancements in computational materials discovery, and Jacqui Cole's collaboration for the Materials Chemistry Horizon Prize on sustainable chemical processes.^[36]^[61] Furthermore, the inaugural ISIS Springboard Awards were presented in March 2025 to three early-career researchers—Shurui Miao, Jennifer Johnstone-Hack, and William Sharratt—for innovative proposals in neutron and muon techniques, fostering talent development.^[62] User engagement continued to expand, with 1,673 unique users accessing the facility in 2025, including 37% students and 214 new principal investigators, reflecting a 73.3% rate of international collaboration.^[3] This activity yielded 559 journal publications involving 3,546 authors and 5.8% industry collaborators, demonstrating the facility's impact across disciplines.^[3]

Long-Term Outlook and Collaborations

The ISIS Neutron and Muon Source's operational lifespan has been strategically extended to at least 2030, ensuring continued UK leadership in neutron and muon research through targeted upgrades and enhancements to the existing facility.^[63] As part of this long-term planning, the science case for a successor facility, ISIS-II, is being developed in consultation with the user community, with key drafts anticipated in 2025 to justify potential advancements such as increased beam power to support higher scientific throughput.^[3]^[9] Decommissioning of the current ISIS facility is projected to commence around 2040–2045, following an expected 60-year operational lifetime, with comprehensive environmental remediation efforts focused on managing radioactive waste and site restoration over subsequent decades.^[64]^[65] In preparation for this transition, ISIS is contributing expertise and hardware to the European Spallation Source (ESS), including the design and delivery of instruments such as LoKI for small-angle neutron scattering and FREIA for reflectometry, to maintain seamless access for UK and European researchers.^[66]^[67] ISIS maintains a robust network of international collaborations through formal agreements and memoranda of understanding, fostering joint experiments, instrument development, and training programs. Key partnerships include long-standing ties with India's Department of Atomic Energy (via Jawaharlal Nehru Centre for Advanced Scientific Research) for neutron scattering and muon studies since 1983, renewed in 2016; a 2024 agreement with Neutrons Canada for beam time access and research proposals; collaborations with Brazil on neutron techniques and the Multipurpose Brazilian Reactor project; a 2025 memorandum with Indonesia's National Research and Innovation Agency (BRIN) for neutron and muon science; skills development under the Newton Programme with Malaysia (2018–2020); an extended agreement with Sweden's Research Council until 2029 for user access and instrument enhancements; ongoing partnerships with Japan's RIKEN, KEK, and JAEA since 1990 for muon facilities and experiments; and a new 2024 strategic partnership with Switzerland under the UK International Science Partnerships Fund for advanced capabilities in neutrons, muons, and X-rays.^[68]^[69]^[70]^[71]^[72]^[73]^[74]^[75] Looking ahead, ISIS envisions enhanced capabilities in quantum science—such as studies of superconductivity and quantum materials—and sustainability research, including low-carbon materials and catalysis, even as global neutron and muon infrastructure faces capacity constraints by the 2050s due to facility closures and limited new builds.^[76] Integration of artificial intelligence for data analysis is expected to play a pivotal role, improving efficiency in handling large datasets from advanced instrumentation and enabling real-time insights.^[76] However, these ambitions are tempered by challenges, including the aging of core infrastructure requiring sustained investment and intensifying competition from facilities like the European Spallation Source and Japan's J-PARC, which could impact user access and resource allocation.^[76]^[77]

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[32]
ISIS and the UK's Modern Industrial Strategy
Oct 30, 2025 · The unique view of muons has also been exploited by Toyota, who have used ISIS to study hydrogen storage systems during cycling. If hydrogen is ...
[33]
BioNTech and EMBL use neutrons and X-rays to progress mRNA ...
Sep 1, 2025 · Carbon Net Zero Research at ISIS Neutron and Muon Source · Tea and ... First neutrons for the MIGDAL experiment at ISIS · Neutrons for ...
[34]
Bioscience Science Highlights - ISIS Neutron and Muon Source
Researchers from China, Manchester and ISIS have used neutrons to gain new insights into peptide self-assembly and the 'polar zipper' mechanism, which could ...
[35]
ISIS Neutron and Muon Source - Science with Impact.
It also includes £0.4 billion of future economic impact up to 2025, generated from research and innovation already completed. ISIS has delivered a healthy ...<|control11|><|separator|>
[36]
(PDF) ISIS Neutron and Muon Source - Lifetime Impact Study
Sep 17, 2019 · This report summarises our main findings from the ISIS Lifetime Impact study; which outlines the economic and social impact of the ISIS ...
[37]
ISIS RSC Horizon Prize win for ISIS scientist David Keen
ISIS scientist David Keen is part of an international team of researchers awarded this year's Dalton Horizon Prize from the Royal Society of Chemistry.Missing: software | Show results with:software
[38]
Diamond scientists win RSC prize for chemistry-aware AI software
This included scientists from ISIS Neutron and Muon Source and the Research Complex at Harwell. The team developed ChemDataExtractor, the first chemistry-aware ...Missing: hybrid glasses
[39]
Target Station 1 - ISIS Neutron and Muon Source
The TS1 project seeks to upgrade key elements of the target station, with the actual work taking place during the long shutdown in 2021/22.
[40]
ISIS GEM
The General Materials Diffractometer (GEM) is used for high intensity, high resolution neutron diffraction and pair distribution function experiments.
[41]
ISIS HRPD
HRPD was constructed on beamline S8 on TS-1 (110 K methane moderator) as part of the “Day 1" instrument suite at ISIS in the mid-1980s. A number of upgrades to ...
[42]
The upgraded Polaris powder diffractometer at the ISIS neutron source
Nov 1, 2019 · This paper describes the design and operation of the Polaris time-of-flight powder neutron diffractometer at the ISIS pulsed spallation neutron source.
[43]
Upgrade of the MARI spectrometer at ISIS - ScienceDirect.com
MARI is a time-of-flight direct-geometry spectrometer located in the first target station at the ISIS Neutron and Muon Spallation Source, Rutherford Appleton ...
[44]
ISIS Osiris
OSIRIS is a spectrometer optimised for very low energy studies and long wavelength diffraction. These studies can provide information on relatively slow ...Missing: station | Show results with:station
[45]
ISIS Engin-X
ENGIN-X is a dedicated engineering science facility at ISIS. The beamline is optimized for the measurement of strain, and thus stress, deep within a crystalline ...Missing: station | Show results with:station
[46]
Vesuvio instrument - ISIS Neutron and Muon Source
VESUVIO was initially designed only to measure nuclear momentum distributions (NMDs) for the lightest elements (H, He) in materials using epithermal neutrons.
[47]
ISIS INES
Contact information for Ines instrument. Location and contact information ... ISIS Instruments. ISIS Instruments · PEARL · Crisp · GEM · NIMROD · Surf · Loq ...Missing: archaeology | Show results with:archaeology
[48]
Neutronics analysis of target, moderators and reflector design for the ...
Dec 15, 2018 · The aim of the Target Station 1 (TS-1) project at the ISIS Neutron and Muon Source is a complete refurbishment of the internals of the TS-1, ...
[49]
Muons at ISIS - PMC - NIH
Once within the synchrotron, the energy of these protons is increased to 800 MeV and split into two orbiting bunches. These bunches are then extracted down ...
[50]
[PDF] Technical description of the Second Target Station
One pulse in five from the ISIS synchrotron will be directed into the target along a new proton beam line. The relatively low proton power will allow target and.Missing: length | Show results with:length
[51]
[PDF] ISIS Target Station 2 Phase II Business Case
Sep 2, 2009 · The ISIS Target Station 2 (TS2) project (Phase I) has provided a second target station with capacity for up to 18 neutron scattering instruments ...
[52]
ISIS LET science
It makes it possible to match the pulse width from the moderator and the chopper to maximise the flux for any given resolution. The resolution is not limited by ...
[53]
ISIS IMAT (Imaging and MaTerials instrument): Technical Details
Time-integrated neutron flux, 4 X 107 n/cm2/sec (for L/D: 250). Diffraction at 90o, Secondary flight path, 2.0 m. , Detector coverage (each of the two ...Missing: TS2 | Show results with:TS2
[54]
Target Station 2 Phase II Instruments - ISIS Neutron and Muon Source
The ISIS Target Station 2 Phase II project is now complete, and details of developments of the four instruments in the Phase II project – LARMOR, IMAT, Zoom ...
[55]
https://royalsocietypublishing.org/doi/10.1098/rsta.2018.0064
[56]
Muons at ISIS | Philosophical Transactions of the Royal Society A
Dec 10, 2018 · Each spill has a repetition frequency of 50 Hz [1]. Some ... At lower momenta, pions are readily rejected using the time-of-flight method.
[57]
https://www.isis.stfc.ac.uk/Pages/emu.aspx
[58]
ISIS EMU - ISIS Neutron and Muon Source
EMU is a 96-detector µSR instrument optimized for zero and longitudinal field experiments, with fields up to 4500G and temperatures from 50mK to 1500K.
[59]
HiFi - ISIS Neutron and Muon Source
The high-field muon instrument at ISIS, called HiFi, provides applied longitudinal fields up to 5T · The magnet is a 5T superconducting split-pair, with high ...
[60]
HRPD-X - ISIS Neutron and Muon Source
- Reclad tunnel connecting HRPD to the target station for better temperature control and insulation ... ISIS High-Resolution Powder Diffractometer. J. Neutron Res ...
[61]
ISIS scientists part of a collaboration that has won the RSC's 2025 ...
Jun 26, 2025 · ISIS scientists part of a collaboration that has won the RSC's 2025 Materials Chemistry Horizon Prize. 26 Jun 2025. No. - · The team, led by ...Missing: hybrid glasses
[62]
ISIS ISIS Springboard Award Winners - ISIS Neutron and Muon Source
Mar 12, 2025 · The ISIS Neutron and Muon Source has presented three early-career researchers with its first ISIS Springboard Awards. · Meet the award winners.
[63]
ISIS Strategy 2030 - Neutrons and muons to advance knowledge ...
ISIS will lead the way in the innovative development and exploitation of neutron and muon sources, science, instrumentation and technology. · Mission: Neutron ...Missing: disciplines | Show results with:disciplines
[64]
[PDF] A LIFE CYCLE ASSESSMENT OF THE ISIS-II NEUTRON AND ...
of ISIS-II (2040-2100) is defined using the expected 60 year lifetime of the current ISIS neutron and muon source. The decommissioning due to radioactive ...Missing: plans | Show results with:plans
[65]
[PDF] The environmental impact of the ISIS-II Neutron and Muon Source
Jan 25, 2024 · o Plans for ISIS decommissioning (2045-2090) o expected radioactive ... • ISIS-II is the next proposed upgrade to the ISIS Neutron and Muon Source.
[66]
[PDF] Annual Review 2022 - ISIS Neutron and Muon Source
The ISIS Industrial Collaborative Research and. Development scheme (ICRD) was established in 2012 and provides a lower risk, more flexible access route for ...
[67]
ISIS LoKI instrument installed and ready for commissioning at ESS
Sep 2, 2025 · A decade of collaboration between ISIS in the UK and ESS has brought LoKI to life. Designed to leverage the unprecedented capabilities of ESS as ...Missing: decommissioning 2040
[68]
ISIS International Partnerships and Collaborations
ISIS has a wide variety of agreements and Memoranda of Understanding (MoU) with other research facilities and organisations around the world.
[69]
India - ISIS Neutron and Muon Source
India became the first ISIS international partner with an agreement signed in 1983 contributing to development of one of the very first ISIS instruments, IRIS.
[70]
Canadian Access to ISIS - ISIS Neutron and Muon Source
A new collaboration agreement between ISIS and Neutrons Canada has been signed to support this programme. Neutrons Canada have a short news item on their ...
[71]
Brazilian Access to the ISIS Neutron and Muon Source
The ISIS Neutron and Muon Source provides 35 instruments, 30 of which are dedicated to neutron techniques; each year it has 3500 user visits, performs 1000 ...
[72]
ISIS and BRIN, Indonesia, partner for neutron and muon science
Jan 7, 2025 · The MoU will strengthen collaboration in neutron and muon science between ISIS and BRIN (the National Research and Innovation Agency, Indonesia)
[73]
https://www.isis.stfc.ac.uk/Pages/Sweden.aspx
[74]
Celebrating three decades of collaboration between RIKEN and RAL
May 29, 2023 · For over 30 years RIKEN and ISIS have been collaborating in a wide range of science using muons – fundamental studies, condensed matter and ...Missing: Brazil | Show results with:Brazil
[75]
Together for Science with Neutrons, Muons and X-rays
Dec 10, 2024 · A strategic partnership between research facilities in the UK and Switzerland has been established by the UK International Science Partnerships Fund (ISPF).
[76]
A Vision for the Future of Neutron Scattering and Muon ...
Typically, reactors are optimized for the production of low energy neutrons (<100 meV), while spallation sources produce a much wider energy band (extending to ...
[77]
ISIS The future of UK neutron science - insights from STFC review
Mar 14, 2025 · It also evaluates the current and future roles of ISIS, ILL and ESS in addressing scientific challenges that rely on neutron facilities, and ...Missing: decommissioning 2040 FREIA